Welcome to community, please go to admin -> Themes -> edit code and look for your language's .json file under Locale folder.
It is also possible that above issue is due to code where you forgot to put | t option which is require to put the right value based on language. In absence of same it defaults to english
Hope this helps!
Right now the Color label is not a fixed label but it is the Variant title mentioned in the product in admin. So we change variant title or put the fix title?
The Color label is derived from the group name which is deribed from user defined tags, you need to rename color tags to get the right name there
instead of Color_Aqua use Kleur_Aqua and instead of Clor_Geel rename Kleur_Geel ....and so on.
Same logic is applied for other groups as well.
Hope this helps
This is an accepted solution.
these are the acceptable prefix for color names for color swap grouping to work correct